In recent years, along with the progress of corporate globalization and the like, non-native speakers of Japanese have had increasing opportunities of writing Japanese text. Accordingly, to provide support to such persons for writing Japanese text, there have been developed text proofreading apparatuses that detect and correct mistakes and improper expressions in created Japanese text. As a text proofreading apparatus, for example, there is commercialized a software application that performs morphological analysis on Japanese text, and based on results of the analysis, automatically proofreads improper terms in text and points out abusage of okuri-gana, conjugational ending in kana added to a Chinese character, and ending of words. In addition, there is suggested a technique for text proofreading in which unified standards for proofreading of differences in wording are defined in advance, and if it is detected that any wording in sentences does not meeting the standards, a writer is prompted to correct the wording. Further, there is a technique for text proofreading under study in which it is determined whether correct particles are used in Japanese sentences based on rules on usage of particles associated with verbs and the meanings of nouns connected to the particles, and if there is any incorrect particle, the particle is automatically corrected to the appropriate one.    Patent Document 1: Japanese Laid-open Patent Publication No. 07-085050    Patent Document 2: Japanese Laid-open Patent Publication No. 05-120275
However, the foregoing text proofreading techniques have problems as described below for example. That is, Japanese text to be proofread may include not only mistakes in okuri-gana and differences in wording that can be corrected by superficial analysis with reference to a dictionary or the like, but also mistakes such as particle errors that are difficult to correct only by superficial analysis on the sentences. For example, for correction of particles, it is a general practice to prepare in advance a dictionary including an enormous amount of organized data of constraint conditions on verbs and nouns for usage of particles. However, this method is intended to determine validity of particles associated with verbs in sentences. Therefore, if there is any error in use of a verb, it is difficult to correct the verb by this method.
Specifically, it is assumed that the Japanese sentence “” is given as a target of proofreading, for example. In this case, in the proofreading method by which the verb “” is not to be changed, it is possible to provide a candidate for correction of a particle such as “”, but it is difficult to correct two particles at the same time (correction of a compound particle error) to “”.
In addition, in the proofreading method by which verbs are not to be changed, it is possible to provide the candidate “” but it is difficult to suggest another possible corrected phrase “”. Such a problem can be solved by providing a text proofreading apparatus with a dictionary for proofreading in which pre-replacement and post-replacement character strings are registered, so as to compare the original text (sentence to be proofread) with the dictionary and automatically correct detected error(s). For example, the foregoing problem can be solved by registering data for replacing the phrase “” with “” in the proofreading dictionary of the text proofreading apparatus. However, in the case of sentences such as “2”, it is difficult by the foregoing method to discriminate between sentences to which the replacement with “” is applicable and sentences to which the replacement with “” is not applicable. As a result, there may arise a problem that words not to be replaced are replaced. This deteriorates accuracy of text proofreading.
Further, the foregoing constraint conditions are in general manually formulated by humans, which requires large amounts of man-hours and time to create a dictionary for proofreading. In addition, there is another problem of variations prone to occur in output from formulators. This contributes to inhibited improvement of accuracy on proofreading of text.